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Updated: Jun 26, 2026
08:41
Generation and Control of Electrohydrodynamic Flows in Aqueous Electrolyte Solutions
Published on: September 7, 2018
Direct observation of a nonequilibrium electro-osmotic instability
S M Rubinstein1, G Manukyan, A Staicu
1Racah Institute of Physics, Hebrew University of Jerusalem, Jerusalem 91904, Israel. robinst@bgu.ac.il
Physical Review Letters
|December 31, 2008
Summary
We visualized predicted instability in ionic conduction from copper sulfate electrolytes into solids. This overlimiting conductance transition is driven by vortical flow, increasing with applied voltage.
Area of Science:
- Electrochemistry
- Materials Science
- Fluid Dynamics
Background:
- Ionic conduction in electrolytes is crucial for energy storage and conversion.
- Understanding electrolyte-solid interfaces is key to designing advanced electrochemical devices.
- Instabilities can limit device performance and lead to failure.
Purpose of the Study:
- To visualize and predict the onset of instability in ionic conduction.
- To investigate the transition from limiting current to overlimiting conductance.
- To understand the role of vortical flow in this transition.
Main Methods:
- Computational modeling and simulation of ionic transport.
- Analysis of current-voltage characteristics.
- Visualization of fluid dynamics at the electrolyte-solid interface.
Main Results:
- Predicted instability in ionic conduction from a binary electrolyte (copper sulfate) into a charge-selective solid.
- Observed current saturation at the limiting current, followed by increased current (overlimiting conductance).
- Identified vortical flow as the mechanism mediating the transition, intensifying with applied voltage.
Conclusions:
- The study visualizes a critical instability in ionic conduction relevant to electrochemical devices.
- Overlimiting conductance is linked to emergent vortical flow, influenced by applied voltage.
- Findings provide insights into managing ion transport at electrolyte-solid interfaces.
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